[PATCH] Remove __SIZE_TYPE__ usage (BZ 33969)

[Joseph Myers]

On Wed, 11 Mar 2026, Adhemerval Zanella Netto wrote:

> On 10/03/26 20:07, Joseph Myers wrote:
> > On Tue, 10 Mar 2026, Adhemerval Zanella wrote:
> > 
> >> The ‘fcntl-linux.h’ and ‘cdefs.h’ changes are straightforward
> >> because size_t is already defined.  The glob.h change uses
> >> stddef.h as other installed headers.
> > 
> > Could you give more details of your analysis for <sys/cdefs.h>, for what 
> > headers under what feature test macros use any of the relevant macros from 
> > <sys/cdefs.h>?  (Since certainly <sys/cdefs.h> is used in lots of 
> > installed headers that don't and can't define size_t in standard C modes, 
> > so the question is when the particular macros therein that would use 
> > size_t themselves get used.)
> > 
> 
> The  __SIZE_TYPE__ is used solely for fortify support, which itself adds
> additional constrains of what compiler needs to provide (__GNUC_,
> __USE_EXTERN_INLINES, __fortify_function). Also, some of the fortify 
> wrappers themselves add an implicit requirement of size_t.

The question is: which installed headers use this fortify support, and do 
all such headers define size_t unconditionally (or, failing that, for all 
conditions under which the fortify support is used)?  For example, 
<string.h> defines size_t, so there is certainly no problem for any use of 
these fortify macros from <string.h>.

-- 
Joseph S. Myers
josmyers@redhat.com